Prototyping of a user interface (UI) is a highly creative process in which it is beneficial to get ideas visualized very fast. There are software products to support these creative processes by allowing creating UI mockups and changing them. However, these tools are either very generic and flexible, which makes them harder to use or very specific, which makes them easier to use but not very flexible. As result, it is very common to use pens, paper, scissors, sticky notes etc. to create and modify UIs.
For instance, after a UI prototype (or a mockup) is created using software-based design tools, the design may be further refined using print-outs, scissors, and glue. Thus a situation may occur where the desired UI design exists only in a paper form. It needs to be digitized and converted into the domain for which the design is being created. For example, various UI elements that are present on paper, such as buttons, fields, etc., need to be converted into UI elements suitable for the target platform. Thereafter, it is still common to change the mockup UI because then is the first time that the mockup can be visualized on its target platform. Even at this stage of the design process a redesign using pen and paper may take place, especially when significant changes to the UI design are required. Merging these processes—software-based UI design and paper-based UI design may be cumbersome and labor-intensive.